Vehicle profiles may be reduced to decrease vehicle size and mass. At the same time the relative size of engine compartments may be reduced to help improve crash ratings, fit improved suspension packages and larger wheels, and/or improve cabin room. However, while vehicle size may be reduced additional technologies may be added to engines to improve fuel economy, performance, and emissions. Consequently, packaging may be a central issue in the engine design process. One such technology which may improve fuel economy, performance, and emissions are cam phaser systems configured to change relative timing of valve actuation and piston reciprocation. Several types of camshaft phasers may be used for mechanical control of the valvetrain such as electric controlled, oil controlled, or cam torque controlled.
US 2013/0025403 discloses a camshaft assembly for adjusting the duration of valve lift having a hollow camshaft and a first cam phaser positioned in the middle of the hollow camshaft and a second cam phaser positioned at an end of a camshaft adjacent to a sprocket.
The Inventors have recognized several drawbacks with the camshaft assembly disclosed in US 2013/0025403. Firstly, mounting one of the phaser's adjacent to the sprocket may increase the likelihood of phaser damage during a vehicle impact. Moreover, the cam phasers may interfere with adjacent components due to their positions. Furthermore, it may be difficult to route oil to the cam phaser positioned in the middle of the camshaft.
The Inventors herein have recognized the above issues and developed an engine system. The engine system includes a drive component coupled to a first end of a camshaft and mechanically coupled to a crankshaft and a cam phaser coupled to a second end of the camshaft and mechanically coupled to and spaced away from the drive component, the cam phaser configured to alter the timing of the camshaft. In this way, the phaser and the drive component are positioned at remote locations, thereby reducing the likelihood of phaser damage during a vehicle collision. In one example, the camshaft may be a hollow camshaft at least partially enclosing a phaser driveshaft coupled to the drive component. In this way, the compactness of the engine system is increased, enabling the profile of the engine to be reduced, if desired.
The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. Additionally, the above issues have been recognized by the inventors herein, and are not admitted to be known.